1. Field of the Invention
The present invention relates to an improved ratchet wheel structure of a ratcheting wrench, more particularly to a ratchet wheel structure using the external diameter of its axial ratchets corresponsive to the external diameter of the ratchet wheel for its production to improve the strength of the pawls of the blocking member which is for latching the ratchets of the ratchet wheel, and to avoid the ratchets from being cracked. The axial ratchet extends directly to the intersection point of the serrated disk of the ratchet wheel and allows an integral formation of the ratchet wheel structure for an easier manufacture and quality inspection.
2. Description of the Prior Art
The traditional ratcheting wrench such as the one described in the U.S. Pat. No. 6,148,695. For simplicity, such invention is depicted and disclosed in FIG. 1. In order to accomplish a smaller volume of the fixing base for the ratchet wheel, the ratchet A1 is disposed in the concession area B in the ratchet wheel A, and its external diameter is smaller than the external diameter of the ratchet wheel so that the ratchet formed is decreased with respect to the width of its wall, and it will reduce its strength. Furthermore, since the ratchets are deep inside the concession of the ratchet wheel, it has stricter accuracy requirement for its manufacture, and is more difficult to manufacture. In the mean time, since the ratchets are designed as an inwardly concave structure, therefore we are unable to inspect the quality of the ratchets by simple non-destructive instrument such as an overhead projector, and such shortcoming makes the inspection more difficult.
Further, please refer to FIG. 2. It shows another embodiment of the U.S. Pat. No. 6,148,695, which tries to solve the above-mentioned problem regarding the thickness of the wall by making the ratchets inside the concession area B as a straight serration A1xe2x80x2 instead of the inwardly concave one, and provides higher accuracy to the manufacturing. Since it just fills up the concession of the ratchets as shown in FIG. 1, the external diameter of the ratchet is smaller than the external diameter of the ratchet wheel. What has been accomplished is just better than the strength of the structure as shown in FIG. 1. Since the ratchets are still deep inside the concession area B, we still cannot perform the quality inspection easily.
In view of the shortcomings of the prior art, which are the subjects of improvements for a long time, hence the inventor of the present invention based on years of experience accumulated from the engagement in the related industry conducted extensive research to resolve the foregoing shortcomings and invented the present invention.
Therefore, the primary objective of the present invention is to provide an improved ratchet wheel structure of a ratcheting wrench, wherein the external diameter of the ratchet wheel is slightly smaller than the hole diameter of the insert hole of the fixing base, and a restricting base is disposed at the bottom of the ratchet wheel. The external diameter of the ratchets is slightly smaller than the diameter of the insert hole on the fixing base, and a restricting base is disposed at the bottom, and the external diameter of the restricting base is slightly smaller than the diameter of the hole at the bottom of the fixing base, and it extends to the intersection point of the ratchets of the ratchet wheel to form a serrated disk. The ratchets are aligned parallel to the axial direction at the middle section of the positioning area and it extends to the intersection point of the positioning area such that the tip of the ratchet is corresponsive to the external diameter of the ratchet wheel. Furthermore, a latching groove is disposed at an appropriate position around the fixing area for latching the C-shape buckle into the latching groove in position, and the ratchet wheel is embedded into the fixing groove of the ratchet wheel such that the serrated disk of the ratchet wheel and the restricting base just fall into the cross base and the restricting hole of accommodating groove for the positioning. The C-shape buckle is then embedded into the inner edge of the insert hole of the accommodating groove such that the ratchet wheel in the accommodating groove will not fall out. Therefore, the ratchet of the ratchet wheel is corresponsive to the external diameter of the ratchet wheel such that the ratchet can keep the minimum external diameter of the ratchet wheel and obtain the maximum effective diameter of the ratchet. When the pawls of the blocking member are engaged with the ratchets, it strengthens the ratchets and avoids them from being cracked.
The secondary objective of the present invention is to provide an improved ratchet wheel structure for a ratcheting wrench, wherein the axial ratchets are disposed at the intersection position of the fixing area and the ratchets, and directly reach the serrated disk such that the ratchet wheel and the ratchets can be formed to allow easy manufacturing. Due to its semi-opened design, it does not need destructive examinations for the quality inspection and it makes the job of quality control easier.
To make it easier for our examiner to understand the objective of the invention, structure, innovative features, and performance, we use a preferred embodiment together with the attached drawings for the detailed description of the invention.